Electric door lock for automobiles



Dec. 6, 1938. c. H4 BRUNS 2,139,183

ELECTRIC DOOR LOCK FOR AUTOMOBILES Original Filed Aug. 19, 1936 Patented Dec. 6, 1938 UNITED STATES PATENT OFFICE Continuation of application Serial No. 96,860, August 19, 1936. This application December 16, 1937, Serial No. 180,180

11 Claims.

I'his invention relates to door locks, especially, electrically controlled locks for automobile doo-rs, and among other objects, aims to provide an improved lock of this character which may be con- 5 trolled from the dash or instrument board of the car, and which will securely lock one or more of the doors of the car independently of the handycontrolled locks usually placed on the inside of each door. Another object is to provide a safety device which, in the event of an accident, will automatically release the electrically controlled locks to permit normal manipulation of the door latches from the inside, thus permitting the r occupants of the car to escape from it. Another L object is to provide a lock of this character which will operate automobile door locks of a known type without requiring any important change in the construction of the locks or doors. Further objects will be understood from the following description of a preferred embodiment of the invention, which is shown in the accompanying drawing forming a part of this specification.

i Fig. 1\is an elevation of a known type of door 5 lock shown with an electrically controlled lock;

Fig. 2 is a top plan view of the lock of Fig. 1;

Fig. 3 is an enlarged vertical section on line 3 3 of Fig. 1;

Fig. 4 is a vertical longitudinal sectional view of a switch for controlling the lock of Figs. 1

and 2;

Fig. 5 is a section on line 5-5 of Fig. 4;

Fig. 6 is a vertical sectional view of the safety switch;

5 Fig. 7 is a section on line 'I-T of Fig. 6; and

Fig. 8 is a wiring diagram showing how the control and safety switches are connected with a source of current to actuate a plurality of door locks.

l Referring particularly to the drawing, there is shown vvan. automobile door lock comprising a plate I0 having a flange II, a bolt I2 movable through the flange, a bolt spring I3 mounted on plate I0 and engaging the bolt, as shown, to thrust i it outwardly to engage the usual keeper (not shown) in the jamb (not shown), a bolt-guiding rivet I4, a slot I5 in the bolt to receive the rivet, and a bracket I6 attached to the plate and carrying the rivet I4. A strap I'l having a slot I8 for a l rivet I9, which is attached to bolt I2, permits remote control of the bolt from a lever (not shown) on the inside of the door (not shown); and the slot I8 permits manipulation of the bolt from the outside door handle (not shown) without aiecting the position of said lever. The outside door handle is attached to a spindle 20, on which there is an eccentric or cam 2I which engages a cam edge 22 on bolt I2 to throw said bolt back against the resistance of spring I3. Ai bracket 23 attached to the plate supports the 5 spindle end and holds the cam in proper position. The lock as so far described is an article of commerce. On plate I0 I mount a pair of op positely polarized electro-magnets 24, by means of a clip or clamp 25 screwed to the plate. l These electro-magnets are connected with wires to a source of current such as a battery 21, as shown in Fig. 8, so as to be energized when a circuit is closed, magnet 24 being the unlocking solenoid and magnet 25 being the locking coil. 1b An armature plate 28 is secured to bolt I2 and extends at right angles thereto, close to the ends of the two electro-magnets; the arrangement being such that whenever either coil is energized, the armature 28 is pulled into contact with the corre- 20 sponding pole piece of the coil, thus thrusting the latching end of the bolt outwardly. This pressure on the bolt insures a dependable action on the part of the non-magnetic dog 29, which is pivoted at 3U on the plate and which has a non- 25 magnetic connection with an armature 3| contacting with either pole of the electro-magnets but at the opposite ends from armature 28. The end of dog 29 engages bolt I2 at one edge or corner, which is cut out, as shown at 32, to re- 30 ceive said end. As indicated in Fig. 1, the dog oscillates between a bolt-locking position (shown in dotted lines) and the bolt-freeing position (shown in full lines) when its armature 3| is oscillated by magnetic attraction of the electro-magnets 24, 25. In order to hold the dog in either position, until it is compelled to assume the other position, a spring 33 is secured to plate I U and has small indentations 33a, either of which is engaged by a s'mall projection 34 (Fig. 3) on the dog. 40

The lock circuits are controlled by a switch preferably mounted on the dash or instrument board of the car, although it may be placed at other points accessible to the driver. It is desirable to control the lock circuits so that the car 45 doors may be locked or unlocked at will, and very quickly in case of an emergency.

The preferred switch comprises a housing 35 which is removably secured to the instrument panel 36 by means of a threaded bushing 3l and 50 nuts 38. Bushing 31 has a central bore, and a rod 39, which passes through the housing, 1s reciprocable through said bore and through the bore of a similar bushing 40 at the other end of the housing. Bushing 4U is secured to the hous- 55 ing by a nut 4l and is aligned with bushing 31; thus bearings are provided for the slidable rod, which has a knob 42 on its outer end to facilitate its movement. An insulating block 43 is secured as by a screw 44 to the rod. 39, and said screw preferably projects through a straight slot 45 in the housing, thus preventing turning of the rod on its axis. The insulating block is provided to make direct contact with one of a pair of contact springs 46, 41 preferably formed from a single strip of a resilient conductor which is secured to the housing by a` contact screw 48. Said contact screw is insulated from the walls of the housing as by providing insulation strips 49, 50 and insulating washer 5|. Two other contact screws 52, 53 have their inner ends so located relative to the ends of contact springs 46, 41 that when the insulating block 43 engages the contact springs, their ends are tightly pressed against the ends of the contact screws; and when the latter are connected in a circuit with the lock of Fig. 1, for instance, as shown in Fig. 8, locking and unlocking of the standard door locks is easily effectedv without manipulation of the usual handles, levers and catches. It will be clear that while the switch of Figs. 4 and 5 is useful for control of the locking system of the invention, various switches of different construction might be used in the combination.

The parts so far described, if properly connected in a circuit with a battery, will permit dash control of one or more of the door locks of an automobile, and thus will make it possible for an adult driver to lock the rear doors of a sedan, for example, to make it impossible for children riding in the back seat to open said doors and perhaps fall out. In case of a serious accident, however, locked doors which cannot be opened by the usual handles, etc., maybe the cause of a fatality. Hence it is desirable to .provide a safety switch which acts entirely automatically, in case of a collision or other accident involving a sudden checking of the momentum of a car, to shortcircuit the dash switch and thus release all the locks controlled by said switch.

In Figs. 6 and 7 there is shown a simple type Ofmomentum-controlled safety switch comprising an insulating body 55, a pendulum 56 and a conductor ring 51 Within the body 55 and connected to a contact screw 58. The body 55 is mounted at any convenient point on the automobile so that the arm of pendulum 56 is substantially vertical. The upper end of the pendulum arm preferably is not suspended, but has a point 59 entering a conically recessed bushing and terminal screw 66 secured to the cover 55a of the body. Thus the pendulum may swing about the point 59 as an axis, to make Contact with ring 51 and close a circuit including the two contact screws 58, 60. Ordinarily, however, swinging of the pendulum is impossible because of a latch consisting of a spring 6i urging a ball 62 into a recess 63 on the bottom of the pendulum body. In case of a collision or the overturning of the car or other major accident, the momentum of the pendulum will be sufcient to overcome the resistance of the latch 62, the pendulum will move into contact with conductor ring 31 to shortcircuit the dash switch, and will remain in contact until thesafety switch is re-set. The short-circuiting action will be clearly understood from Fig. 8. Re-setting of the safety switch-may; be accomplished either by removing cover-55a orby centering the pendulum by means of instruments thrust through perforations 64 in the bodyfwalls.

From Fig. 1 it will be clear that unless the bolt I2 is thrust outwardly as far as it will go, the end of dog 29 will not be seated in the cut-out or notch 32 and hence the bolt will not be locked against retraction, and will not, under those circumstances, lock the door at all but will merely yieldably latch the door. However, with the parts as shown and described, the armature 28 will push the bolt outwardly to 'full locking position whether the dog 29 is in the upper position as illustrated (which frees bolt I2) or is in the lower position shown in dotted lines. 'Ihis is` because one of the electro-magnets always attracts the armature, if either circuit is closed by the dash switch 39, 52, 53, the other electro-magnet being then dead or de-energized (but not negatively energized). The result is that the bolt l2 is actually pushed outwardly when the dog 29 is moved upwardly to bolt-releasing position, and is also pushed outwardly when the dog is swung downwardly forcibly to engage and lock the bolt at 32. This action is of great practical importance because it has been found that when a lock has been in use some time on an automobile door, for example, the bolt may stick, i. e., will not attain its full locking position. Of course the bolt of the preferred form of the present invention must be thrust outwardly fully if the dog is to lock the bolt, and if said dog is to move freely out of the cut-out 32'. In short, the described arrangement of a pair of electro-magnets, armature, dog and bolt absolutely assures dependable action; the bolt will always be unlocked when the switch is moved to the door-unlocking position, and the bolt will inevitably be locked against any movement whatever when the switch is moved to door-locking position. It will be clear, further, that no power from the source of electricity is employed except in moving the dog into its alternative positions, and in moving the bolt outwardly fully at the same moment the dog is actuated. The indentations 33a in the spring 33 hold the dog in either of its positions without assistance from the source of electric power. This makes for economy of power consumption, which is important in these days of heavy drains on automobile batteries due to car radios and other accessories.

The present. invention provides appartus attaining all the objects mentioned above. All the parts are inexpensive, are not likely to get out of order, and are easily installed. 'By means of the invention a sedan is rendered as safe as a coach.

This application is a continuation of abandoned application Serial No. 96,860 filed Aug. 19, 1936, for Electric door locks for automobiles.

Obviously the present invention may be embodied in several forms neither shown nor described. Also the invention may be applied to various closures and is not necessarily limited to use on automobiles.

Having described an embodiment of the invention, what I claim as new and desire to secure by Letters Patent is:-

1. An automobile door lock comprising, in combination, a spring-actuated bolt; a dog adapted to engage said bolt to hold the same against movement toward door-releasing position; electro-magnetic means for governing said. dog; a source of current in circuit with said electromagnetic means; a switch for controlling said circuit; and a momentum-actuated safety switch in said circuit adapted to short-circuit the control switch whenever there is a sudden'and violent change in the momentum of the automobile.

2. An automobile door lock comprising, in combination, a spring-actuated bolt; an electromagnetic lock engageable with said bolt; a switch connected in circuit with said lock so that said lock engages or disengages the bolt at the will of the operator; a source of electric current; and a safety switch so constructed and so placed in the circuit as automatically to release said lock when there is a sudden, Violent change in momentum of the car. l

3. An automoble door lock comprising, in combination, a spring-actuated bolt; a source oi current; a pair of voppositely polarized electromagnets in circuit with the source of current; an armature adapted to engage one of the poles of said electromagnets as they are separately energized from the source of current; a switch so connected in the circuit as to permit such separate energization; a dog which is connected to and swung by movement of said armature into engagement with said poles; said bolt and dog directly engaging each other when the bolt is thrust into locking position, so that the dog holds the bolt in said position and prevents retraction thereof; and a safety switch in the circuit so connected, constructed and arranged as to short circuit the switch which energizes the electromagnets Whenever there is a sudden and violent change in the mometum of the automobile.

4. A lock of the class described comprising, in combination, a. locking bolt; a dog adapted to engage said bolt to prevent ordinary manipulation of the bolt; electro-magnetically controlled means to operate said dog; a source of current for actuating said means; a rswitch for contro-lling said means; said bolt having an armature attached thereto; the electro-magnetically controlled means comprising two oppositely polarized solenoids either of which, when energized, attracts said armature to tend to move the bolt as far as it will go into locking position.

5. A lock of the class described comprising, in combination, a slidable bolt; a. spring tending to move the bolt to full locking position; means to limit movement of the bolt in either direction; an armature fast to the bolt; a pair of electromagnets so placed that either when energized, attracts the armature to move the bolt outwardly as far as possible; a source of electric energy; circuits including a .switch connecting the source of electric energy with the electromagnets so that the electromagnets are alternatively energized; a dog adapted to directly engage said bolt to lock it against movement and also adapted, when moved toanother position, to release said bolt to permit it to reciprocate; and an armature attached to said dog and adapted tobe moved by the electro-magnets alternatively to bolt-locking or bolt-freeing position.

6. The invention according to claim 5, wherein, the bolt has a cut-out to receive one end of the dog, which is of non-magnetic material and which is pivoted near the other end.

7. The invention according to claim 5, wherein means are provided to hold the dog mechanical ly but yieldably in either of its positions, so that the source of. electric current is needed only to move the dog from one position to the other.

8. A lock comprising, in combination, a slidable bolt; a handle adapted to control the bolt; a spring tending to move the bolt in one direction; a dog adapted to be moved to lock or release said bolt; said dog locking the bolt by direct engagement therewith but capable of locking only when the bolt is moved to the fullest extent permissible in the direction it is urged by the spring; said bolt being freely movable by the handle when the dog is in bolt-releasing position; and operatorcontrolled electro-magnetic means so constructed and arranged as to move the bolt forcibly in the direction it is urged by the spring and simultaneously moving the dog into either bolt-locking or bolt-releasing position as controlled by the operator. v

9. The invention according to claim 8 wherein the dog is held in its bolt-looking or leasing position by a frictional holding device which yields to the superior force of the electro-magnetic means but otherwise maintains the dog permanently in one position or the other, so that electric power is unnecessary except when the dog is shifted.

10. A lock comprising, in combination, a bolt which is Withdrawable by a handle and normally extended into closure-locking position by a spring; a lock for the bolt; and operator-controlled electro-magnetic means adapted to operate the bolt lock to release or hold the bolt against movement, as desired, and simultaneusly to thrust the bolt in the direction in which it is urged by the spring, said electro-magnetic means being incapable of thrusting the bolt in any other direction.

11. The invention according to claim 10, wherein said bolt lock positively locks the bolt against retraction by any other member; the circuit of said electro-magnetic means being open at all times except when the bolt lock and bolt are being moved by electro-magnetic energy.

CLARENCE H. BRUNS.

Patent N. 2,159,185.

CERTIFICA'I'EYOF QORRECTION. A vDecember 6, 1958.

CLARENCE H. BRUNS. It is hereby certified that error appears in the printed specification 'of the above numbered patent requiring correction as 'follows z Page 5. second column, line 52, claim 9, for "leasing" readl releasing; and that the saidv Letters Patent shouldbe read with this correction therein that the same may conform to the record of the case in the Patent Office. Signed and sealed this 51st day of January, A. D. 1959.

Henry Van Arrsdale -(Seal) Acting Commissioner of Patents. 

